"We have got complaints about foreign funding to AAP and are probing the matter...Investigations take time and we are looking for the source behind the funding," Shinde said.

AAP's chief ministerial candidate Arvind Kejriwal, however, said the funds of Congress and BJP should also be probed.

AAP leader Kumar Vishwas challenged the government to prove them guilty.

"There's no point in making allegations against us. I challenge both the Congress and the BJP to prove us guilty. We receive all our funds in a transparent manner," he said.

"Both the parties are sacred of us," he added.

The debutant AAP appears to have dimmed the prospects of both the Congress, which has been ruling Delhi for the past 15 years, and the opposition BJP which hopes to gain from a strong anti-incumbency factor.

AAP ready for probe

AAP said that it is ready for a government probe into its funding, but demanded that Congress and BJP also submit themselves to the same scrutiny.

"We welcome the government's order into our funding. We demand that the government also investigate into the funding of Congress and BJP," AAP convener Arvind Kejriwal said.

AAP has collected around Rs 19 crore till November 8 as donations from 63,000 people, including a host of NRIs.

Home Minister Sushilkumar Shinde said that the inquiry has been ordered against AAP on receiving complaints regarding alleged foreign funding for it.

"Complaints have come to me. We are probing the matter. ...from where the funds are coming, from which country, what is the source etc. We are trying to find out all these," he said.

The Home Minister, however, said such a probe takes time and indicated that the outcome of the investigation may not come before the Delhi assembly elections scheduled to be held on December 4.

Kejriwal demanded that "the probe report should be out within 48 hours after the probe ends."

AAP, while raising doubt over "swiftness" shown by the government for probe, said "in past 65 years, has Congress ever demanded probe into BJP's funding?"

The party leaders also said the timing of the demand for probe indicates that Congress and BJP were "hand-in-glove". "BJP leader Arun Jaitley had raised the issue of AAP receiving funds from overseas. At the same time, Delhi Chief Minister Sheila Dikshit is also demanding probe into our funding. It seems that Congress and BJP are jointly making a strategy on how to attack AAP," a party leader said.

Dikshit had yesterday questioned the source of funding of AAP, whose main election plank is to check corruption and which has been relentlessly attacking the Congress Chief Minister and her government on the issue.